Supplementation of Vitamin C Reduces Blood Glucose and Improves Glycosylated Hemoglobin in Type 2 Diabetes Mellitus: A Randomized, Double-Blind Study
What this study found
Vitamin C added to metformin improved glycemic control over 12 weeks. In the vitamin C arm, fasting blood glucose fell from 157.63 ± 3.13 to 141.18 ± 3.81, postprandial blood glucose from 222.24 ± 3.16 to 206.69 ± 3.31, and HbA1c from 8.26 ± 0.09 to 7.80 ± 0.08, while plasma ascorbic acid increased from 0.26 ± 0.008 to 0.45 ± 0.01. Between-group comparisons at 12 weeks were significant for FBG, PPBG, and HbA1c (all P < 0.05) and for plasma ascorbic acid (P < 0.001). The authors concluded the combination was well tolerated and may be a useful adjuvant therapy for glycemic control in type 2…
- Study & population
- Randomized, double-blind study in adults 30 to 60 years old with type 2 diabetes mellitus treated with metformin in an outpatient setting in Nagpur, India.
- Intervention
- Oral vitamin C (ascorbic acid) 500 mg twice daily for 12 weeks, given as an add-on to metformin 500 mg twice daily.
- Key limitation
- The study was short, single-center, and relatively small, with only 33 participants in the active vitamin C arm.
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Open PDFOriginal abstract
No study has ever examined the effect of vitamin C with metformin on fasting (FBS) and postmeal blood glucose (PMBG) as well as glycosylated hemoglobin (HbA1c) in the treatment of type 2 diabetes mellitus (DM). The goal was to examine the effect of oral vitamin C with metformin on FBS, PMBG, HbA1c, and plasma ascorbic acid level (PAA) with type 2 DM. Seventy patients with type 2 DM participated in a prospective, double-blind, placebo-controlled, 12-week study. The patients with type 2 DM were divided randomly into placebo and vitamin C group of 35 each. Both groups received the treatment for twelve weeks. Decreased PAA levels were found in patients with type 2 diabetes mellitus. This level was reversed significantly after treatment with vitamin C along with metformin compared to placebo with metformin. FBS, PMBG, and HbA1c levels showed significant improvement after 12 weeks of treatment with vitamin C. In conclusion, oral supplementation of vitamin C with metformin reverses ascorbic acid levels, reduces FBS, PMBG, and improves HbA1c. Hence, both the drugs in combination may be used in the treatment of type 2 DM to maintain good glycemic control.